If $Q = 5+2i$, $E = i$, and $D = 5-2i$, find $Q\cdot E \cdot D$.
Solution: \begin{align*}
QED &= (5+2i)(i)(5-2i)\\
&=i(25-(2i)^2)\\
&=i(25+4)\\
&=\boxed{29i}.
\end{align*}